U.S. Pat. No. 6,228,033 B1 discloses an apparatus and a method for measuring three important physiological systems, circulations, breathing, and body water compartments, of a patient. More specifically an apparatus and a method for a continuous simultaneous/synchronized and noninvasive measurement of heart pump function, elastic properties of the vascular system, systemic vascular resistance, breathing capacity, and body water compartments through the combined use of bioimpedance and continuous blood pressure measurement techniques and, optionally, spirometry and/or plethysmography are disclosed. This apparatus and method need a large number of sensors for measuring the different properties of a patient.
While on the one hand it seems to be a reasonable approach to use a multitude of measurements with a large number of sensors, this may easily become a totally overloaded system. A large number of sensors leads to an extremely complicated handling of the system. In particular, in Personal Healthcare applications the patients do not exhibit sufficient medical or technical training and often have impaired vision and reduced motor skills, so they are not able to use properly a system with such a complicated handling.